Of all the extensions of experience that games provide, from puzzle-exploits with cartoon unicorns to unrepentant radioactive horrors, it’s the sandbox gangster sims of the GTA series that are the most voluminous and detailed. These open-ended tales within modern cities come complete with their own world: a world of fisticuffs, automotive action, gunplay, fashion, romance, intrigue, comedy, lunacy, drunkenness – the GTA games are more than the sum of their substantial parts.

These are games that set out to be huge, not simply in popularity, but in their content. Rockstar build miniature worlds, and the details they burn into them are startling. GTA IV is no exception: this huge game is its details. It brims over with them, as if the Rockstar team were out of control and had to be actively constrained from their ceaseless, imaginative world-building. Walk down a street and you can’t help being impressed with the litter in the alleyways, the changing weather, or the absurd satirical chatter that goes on between pedestrians.

This is a vast game environment without peer. Even MMOs are cowed by its breadth and life. Sprawling, funny, grim, consistent, violent, even sexy: it is as alive and human as all great games would aspire to be. People who’ve compared this game to Goodfellas and Citizen Kane are kind of missing the point: it’s not the story that the world contains that matters, it’s the world that contains the story. Rockstar have realized that if they build an impressive enough cityscape for the action to take place in, then everything else takes care of itself. In this case, their city is impeccable.

As for what goes on in that world, we have two words for you: music and murder. They might not be the two words that sum it up for you, but they were for us. You’ll see what we mean as soon as you start cycling through the radio stations in any of the many vehicles you’ll end up appropriating. From Chet Baker to Suzie Q to Aphex Twin: the soundtrack alone is a heterogeneous sausage and mash of our musical culture. Chasing down bikers while listening to smoky ambient electronica, or simply getting down with the ‘news’ from the Liberty City area is entertainment in itself. At one point we cruised up to the pier and found ourselves listening to jazz while watching the sun set. How many other games can lay claim to moments like that?

If anything is true of this game, it’s that few people will take quite the same thing from it. There is so much possibility crammed into GTA IV that everyone finds something for themselves. Whether or not you enjoy the ludicrously told, fantastically voiced plot of revenge and disappointment is almost irrelevant: GTA IV’s sandbox approach means there’s a mad zoo of videogame media entertainment on offer, and there’s almost no chance of failing to come away with something of value. From comedy shows to satirical TV of the lowest order, from high-falutin’ pop music to down and dirty hip-hop, from vicious street violence to ten-pin bowling: Grand Theft Auto IV is pumped up and seething with material. That alone makes it worth playing.

Anyway, that tale of revenge and disappointment: it’s the story of Niko Bellic, the stony-faced protagonist into whom you pour your actions. GTA IV places you in the life – partly in control but partly as spectator via cutscenes – of this Balkan immigrant to the United States. He is a profoundly damaged human being: dehumanized by war. He wants love, comforts, comradeship, but he does not flinch at astonishingly cold violence. As in the previous games, it gives your adventures something of a split personality, although it seems all the more pronounced with Niko. He’s genuinely likeable, despite barely seeming to notice that he slaughters anyone who crosses him, or kills just because various shady folk ask it. That’s where the ‘murder’ of ‘music and murder’ comes in. You can’t get away from it: you’re going to kill people. A lot of people. It doesn’t make a lot of sense, but hey, it’s amazingly entertaining. And it has a great soundtrack.